diff --git a/comfy_api/v3/helpers.py b/comfy_api/v3/helpers.py
index 77a0aa898..019c725f4 100644
--- a/comfy_api/v3/helpers.py
+++ b/comfy_api/v3/helpers.py
@@ -5,7 +5,10 @@ def first_real_override(cls: type, name: str, *, base: type) -> Optional[Callabl
     """Return the *callable* override of `name` visible on `cls`, or None if every
     implementation up to (and including) `base` is the placeholder defined on `base`.
     """
-    base_func = getattr(base, name).__func__
+    base_attr = getattr(base, name, None)
+    if base_attr is None:
+        return None
+    base_func = base_attr.__func__
     for c in cls.mro():                       # NodeB, NodeA, ComfyNodeV3, object …
         if c is base:                         # reached the placeholder – we're done
             break
diff --git a/comfy_api/v3/io.py b/comfy_api/v3/io.py
index 60517c0a2..c2733bf14 100644
--- a/comfy_api/v3/io.py
+++ b/comfy_api/v3/io.py
@@ -1115,8 +1115,6 @@ class ComfyNodeV3:
         """Optionally, define this function to fingerprint inputs; equivalent to V1's IS_CHANGED."""
         raise NotImplementedError
 
-    fingerprint_inputs = None
-
     @classmethod
     def check_lazy_status(cls, **kwargs) -> list[str]:
         """Optionally, define this function to return a list of input names that should be evaluated.
@@ -1133,8 +1131,6 @@ class ComfyNodeV3:
         """
         return [name for name in kwargs if kwargs[name] is None]
 
-    check_lazy_status = None
-
     @classmethod
     def GET_SERIALIZERS(cls) -> list[Serializer]:
         return []
diff --git a/execution.py b/execution.py
index 844e34cee..bfddc0ada 100644
--- a/execution.py
+++ b/execution.py
@@ -54,7 +54,7 @@ class IsChangedCache:
         class_def = nodes.NODE_CLASS_MAPPINGS[class_type]
         has_is_changed = False
         is_changed_name = None
-        if issubclass(class_def, io.ComfyNodeV3) and getattr(class_def, "fingerprint_inputs", None) is not None:
+        if issubclass(class_def, io.ComfyNodeV3) and helpers.first_real_override(class_def, "fingerprint_inputs", base=io.ComfyNodeV3) is not None:
             has_is_changed = True
             is_changed_name = "fingerprint_inputs"
         elif hasattr(class_def, "IS_CHANGED"):
@@ -411,7 +411,11 @@ def execute(server, dynprompt, caches, current_item, extra_data, executed, promp
                 obj = class_def()
                 caches.objects.set(unique_id, obj)
 
-            if getattr(obj, "check_lazy_status", None) is not None:
+            if issubclass(class_def, io.ComfyNodeV3):
+                lazy_status_present = helpers.first_real_override(class_def, "check_lazy_status", base=io.ComfyNodeV3) is not None
+            else:
+                lazy_status_present = getattr(obj, "check_lazy_status", None) is not None
+            if lazy_status_present:
                 required_inputs = _map_node_over_list(obj, input_data_all, "check_lazy_status", allow_interrupt=True, hidden_inputs=hidden_inputs)
                 required_inputs = set(sum([r for r in required_inputs if isinstance(r,list)], []))
                 required_inputs = [x for x in required_inputs if isinstance(x,str) and (